Originally Posted by 8VETTE7

When you install a CLB you disconnect the lock motor from the circuit so the column will never lock again. CLB itself doesn't disable the lock, istaller does when they disconnect the lock motor (required) to install the CLB. The CLB is simply an electronic relay that when sent a signal by the BCM turns that signal around back to the BCM thus emulating the "completed" signal that the lock motor would send. The BCM needs the completed signal so that it has confirmation the column is in the state requested. ie either locked or unlocked. Without the completed signal the BCM would signal the PCM to enable fuel shutoff and when you attempt to drive the car the fuel gets shutoff at 2 mph.

Pull key message is related to the column lock system. Many things can cause the message but a weak or bad battery or loose or dirty battery connections are the most common causes. Internal electrical failure of the lock cylinder can also cause the message as can poor/bad grounds. Shutting the car off and not removing the key and then restarting the car is another cause and there are some other possible causes. None the less it is related to the column lock system.

Just because your column does not lock does NOT guarantee that you have a CLB installed. Several things can be the cause. One is that your car received variation 04006C of the GM Column Lock recall service which replaced the lock ring with one that is smaller in diameter and prevents the column from locking. Another is an electrical problem/failure of the column lock electronics that prevent the lock motor from locking/unlocking the column. In most of those failures the fuel shutoff would occur preventing you from driving the car. But a pervious owned may have had the fuel shutoff speed reprogrammed to a high number like 200mph. I'm assuming that you are not the original owner of the car and therefore have no idea of the history of what was done to the column lock system by either GM or previous owners.....